GHSA-v36g-jcw9-x7cw: pydantic-ai (CVE-2026-107287)

Package	Ecosystem	Affected	Fixed in
pydantic-ai	PyPI	>=1.77.0, <1.107.7 \|\| >=2.0.0b1, <2.52.0	1.107.7, 2.52.0
pydantic-ai-slim	PyPI	>=1.77.0, <1.107.7 \|\| >=2.0.0b1, <2.52.0	1.107.7, 2.52.0

Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

Pydantic AI (packages pydantic-ai and pydantic-ai-slim) versions 1.77.0 up to 1.107.7 and 2.0.0b1 up to 2.52.0 are affected. When an agent's local web-fetch tool converts attacker-controlled nested HTML, the conversion can consume excessive CPU and memory and delay other work in the process. Upgrade to pydantic-ai or pydantic-ai-slim 1.107.7 or 2.52.0. If you cannot upgrade, avoid local web fetching of attacker-controlled HTML.

Written 1 Nov 2026.

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
6.5	Medium	3.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H	CNA (GitHub_M)

CISA KEV Not listed.
EPSS 0.0028, the 20th percentile, on 7 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

31 Oct 2026, 14:08 UTC First seen by agentprime
31 Oct 2026, 14:08 UTC Confirmed by OSV

Sources

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.